Continuous sun blue-printing machine.



P. G. FORREST. CONTINUOUS sun BLUE PRINTING MACHINE.

APPLICATION FILED APR. 26, 1912. I

' Patented Sept. 2, 1913.

3 SHEETS-SHEET}.

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P. 0. FORREST.

CONTINUOUS SUN BLUE PRINTING MACHINE.

APPLICATION FILED APR.26, 1912.

.Patentd- Se t. 2, 1913.

3 SHEETSr-SHEET 2.

8 mum x 501 FQ O. FORREST.

CONTINUOUS sun BLUE PRINTING MACHINE.

APPLICATION FILED APR. 26, 1912. 1,071,724; Patented Sept. 2, 1913.

3 SHEETSSHEET UNITED STATES PATENT OFFICE.

FREDERICK CHARLES FORREST, SACRAMENTO, CALIFORNIA.

CONTINUOUS SUN BLUE-PRINTING MACHINE.

Specificationof I 'ettfers Patent.

Patented Sept. 2, 1913.

Application filed April 26, 1912. Serial No. 693,400.

of the invention is not only to print upon 15.

the paper but to wash and fix and drythe prints, the prints coming from the machine complete and ready for use.

' There are a number of blue printing machines, what are known' as the continuous type in which the printing is done by artificial light, said devices being usually constructed for use in connection with an electric light. For printing purposes sun light is far superior to any artificial light, and by reason of its strength the prints can be made much more quickly than by artificial light, thus enabling a sun printing machine to turn out a greater amount of work in a given time than a machine constructed for use in artificial light only.

It is of course understood that artificial light can be employed in connection with my machine, and in this respect it differs from most of the continuous blue print machines which are upon the market as they are constructed so that artificial light only can be employed.

The invention consists of the novel features of construction hereinafter described, set forth in the claims and shown in the accompanying drawings, in which;

Figure 1 is aside elevation. Fig. 2 is a vertical section. Fig.3 is a front view, parts being broken away and shown in section. Fig. 4: is a plan view of the upper rear portion of the machine, a glass being shown in section. Fig. 5 is a plan view of alower front corner portion of the machine. Fig. 6 is an enlarged detail sectional view of the lower portion of a curved glass. Fig. 7 is a detail view illustrating certain belts in a drying compartment.

In constructing the device, I employ suit able upright frames 1, substantially triangular in shape and provided in their upper front portions with downwardly and forwardly curved side members 2. These form side members of a frame in which is ar ranged acurved glass 3. A suitable box 4 is carried at the top and rear of the frames 1 and in such boX is adapted to be ournaled a roll of blue print paper 5. The box is suitably slotted as shown at 6 in order that the paper may run therefrom.

The construction of the rest of the device w ll be most readily understood by considering the same in connection with the manner of its operation. v

The machine is first situated so that the glass 3 is facing the sun, and it is preferred to arrange the device in a room and permit the sun light to enter through a suitable opening, the rays of light striking squarely upon the glass 3. In order to obtain asub dued light upon the rear portion of the machine, screens, sheets or curtains may be arranged upon opposite sides 'of the same. After the paper 5 is drawn through the opening 6 and the box 4-, the end is secured to narrow belts 7, which draw the paper through the various parts of the machine. Of course any desired means can be employed for getting the paper started through the machine, but the most convenient means is to clamp the free end of the paper to a rod 7, then secure the rod to the belts by any desired or convenient means. The machine is then set in motion as will be hereafter described and as the blue print paper gradually works down beneath the glass the tracing 8 carrying the drawings to be printcd is placed in position between the glass 3 and the blue print paper. A continuous belt 9 travels over a series of rollers. 10 and 10 and firmly presses the tracing 8 of the blue print paper 4: against the under surface of the curved glass 3. I prefer to make the roller 10 adjustable so that it can be used for tightening the belt 9. In order to lengthen or shorten the exposure I provide a curtain 11, which curtain is adapted to slide over the face of the glass 3, lying at the lower end of the glass when rolled up. The curtain is connected to a slidable bar 12,

provided with rollers-13, which travel in are placed. The exposure to the sunlight pressed rods 15, which also engage said grooves and hold the curtain. in an adjusted After the blue print paper passes over the i lower pulley 10 and leaves the belt 9 it is carried by the narrow belts 7 beneath a series of rubber fingers 16 carried-in a row transversely across the lower front portion of the frame and below the exposure glass These fingers separate the tracing from .the blue print and after being brushed off the print it falls in folds upon thefront of a casing 17, which forms the lower front portion of the machine, and at an opening in the top of which the rubber fingers 16 is completed when the paper leaves the lower roller 10 and the blue print paper 1s now ready to be washed. The washing apparatus comprises two perforated water. .pipes 18, whlch arearranged in the casing 17: To carry the paper into close proximity to-the pipes 18 I employ an endless belt-W19, which runs over rollers 20 and 21 mounted in the. frame 17, a deflector plate 22 being arranged between said rollers, and serving to protect the rear of theframe 17 from any water which may get past the blue print "paper. The blue print paper passes around the lower roller 21 and travels upwardlyand by the time it reaches a small ro-ller 23 most 'of the water has drained th e, from.

In making that class of prints known as white line prints, it is not necessary to employ a fixing solution, and the paper would therefore travel from the roller 23 over a roller 24 and out through the rear of the frame 17 to the drying compartment. But where a blue line print is to be madefit, is necessary to give it a bath in afixing solution after being washed. This solution is held in a tray 25 in the frame 17. This tray is adapted to be raised and lowered by hand, and by elevating the same the paper traveling under the roller 24 will be submerged in the fixing bath. i

It will be noted that the narrow belts make a complete circuit of the deyi'ce running from the upper roller 10 downwardly over the lower roller 10, then over the rollers 20,

21, 24, both rollers 31, to the roller 32, over the roller 33, andback to the upper roller- I roller 32 andthc second roller 31, the vbelt 7 provided with burners and a.suitable'hoodhaving a broad flat" top' above which the paper fastens. Arranged above the paper is a condensing hood 28 around the interior of which is a trough 29 so that steam or moisture rising from the paper and condensed upon the underside of said hood will run down into said trough instead of falling back upon the paper. To support the paper through the drying compartment- I cannot employ wide belts as in the case of belts 9 and 19 andI therefore employ a'large numers 31'. By employing'these narrow belts spaced apart the heat radiated from the top of the burner: casing 27 can pass between said belts and come into contact with the underside of the blueprint paper. After passing above the burner and below the hood the paper passes out at the rear of the machine between one of the rollers '31 and the pulley 32, and the belts 7 continuing.

upwardly and over another pulley 33, and thence back over the upper roller 10. It /will' b e noted therefore that the continuous belts 7 carry the blue print paper through the entire machine and lead it successively from the loelt 9 to the belt 19 and thence to thebelts 36. In order to run the belts a.

ber of narrow belts 30 which run over roll.

suitable motor 34having on the motor shaft a pulley 34 is employed and a friction disk 35 on a shaft 38 is driven from the pulley 34 and a second friction disk 36 is arranged parallel to the disk 35 but with its shaft 37 ,in a lower plane than the shaft 38. A nonrotatable ,vertical shaft 39 carries an adjustable 'frictio wheel 40 loose upon the shaft the peripheryof which travels upon the sides'of the disks 35 and '36. The friction wheel 40 is held between collars 40" secured upon the shaft 39 by suitable setscrews: A spring 38 onshaft 38 holds the disk 35. against the friction wheel 40. Upon the shaft 37 is formed-a worm 41, which meshes witha gear wheel 42 fixed on a "sprocket wheels and transmit motion from r the lower roller 10 to the lower roller 20.

A second sprocket wheel 46' is mounted on the shaft 42 of the gear wheel 42 and a sprocket chain 47 runs from said sprocket to a pointer52 which slides along a' scale 53- laid off upon a rear side member of the frame 1, said scale indicating the speed with V which the blue print paper is being fed to the machine.

- To tighten the belt 9 I provide the roller 10 with adjustable bearings a'sshown at 54. Similar bearings 55 are provided for the lowest roller 31 in order to regulate tension of the belt 30.

It will be noted that the washing device is so constructed that the blue print paper is sprayed only. upon the sensitized side, and consequently as only one side of the paper is wet it will dry more quickly than if it was drawn through a bath and both sides wet.

It Willi-also be noted that as the'paper passes to the drying compartment the exposed and sprayed side will be downward and consequently toward the heater, so that the heat rediated from the top of the heatin casing will act directly upon the wet side of the blue print. This also assists in causing the paper to dry very quickly. It

i M will also be noted that by regulating the speed at which the blue print paper and the tracing arecarried through the machine the. length-of exposure, that is the time occu pied in passing beneath the glass 3 will'be regulated. Furthermore by means of the curtain the paper can be more or less shaded,

thereby allowing for variations in the strength ofthe light caused by the passing of small clouds, thus making the exposure practically uniform for all parts of the sheet. I

lVhat I claim. is:

1. In a machine of they kind described comprising an exposure, a washing and a drying compartment, continuous belts running through all of said compartments and adapted to carry a sheet of blue print paper successively through said compartments, a

' tracing paper being carried through the exposure compartment and a series of rubber lingers arranged at the entrance to the Washing compartment and adapted to brush the tracing paper from the blueprint paper.

2. .A blue printing machine comprising a curved frame, a curved glass plate in said frame, narrow belts adapted to travel beneath the marginal portions of said frame and to carry asheet of blue print paper and a tracing through said exposure'compartment, and a continuous belt adapted to travel beneath said glass and to hold the blue printpaper and the tracin paper in close. contact with said glass, an

slidably mounted upon the outer face of said glass.

a curtain 3. A printing device of the kind described comprising an exposure compartment, a washing compartment and a drying compartment, a series oi continuous belts-.arranged in each compartment, and adapted to receive'a sheet of blue print paper and support the same while passing successively through said compartments, and continuous narrow belts adapted to travel through all of the compartments and convey the blue print paper from one compartment to the other.

4. A printing device of the kinddescribed comprising an exposure compartment, a. Washing compartment and a drying compartment, means for conveying a sheet of blue print paper successively through said compartments, and a fixing bath arranged between the washing and drying compartments and adapted to be moved into or out ofengagement with said paper.

5..A blue print device of the kind described comprising exposure, washing and drying compartments, means for feeding a sheet of blue print paper through all of said compartments, the sensitized side of. said paper belng uppermost 1n the exposure compartment and being upon the underside in the drying compartment and means arranged in the washing compartment for spraying the sensitized side of said paper only.

. 6. A device of the kind described compriscompartment, continuous belts adapted to convey a sheet of blue print paper suc- FREDERICK CHARLES FORREST.

Witnesses:

L. J BRATCHER, H. W. LEONARD.

'ing an exposure, a washing and a drying 

